absolute-pos(t = 0, r = 0, b = 0, l = 0)
  top t
  right r
  bottom b
  left l
fixed-pos(t = 0, r = 0, b = 0, l = 0)
  absolute-pos(t, r, b, l)

clearfix()
  &:after
    content ""
    display table
    clear both
// normalize()
//   margin 0
//   padding 0
//   list-style none

word-break()
  word-break break-all
  word-wrap break-word
word-ellipsis()
  white-space nowrap
  overflow hidden
  text-overflow ellipsis

hairline-common(direction, color)
  content ''
  position absolute
  z-index 2
  background-color color
  transform-origin 100% 50%
  if direction == top
    transform scaleY(0.5) translateY(-100%)
    @media (min-resolution: 3dppx)
      transform scaleY(0.33) translateY(-100%)
  else if direction == bottom
    transform scaleY(0.5) translateY(100%)
    @media (min-resolution: 3dppx)
      transform scaleY(0.33) translateY(100%)
  else if direction == left
    transform scaleX(0.5) translateX(-100%)
    @media (min-resolution: 3dppx)
      transform scaleX(0.33) translateX(-100%)
  else if direction == right
    transform scaleX(0.5) translateX(100%)
    @media (min-resolution: 3dppx)
      transform scaleX(0.33) translateX(100%)

hairline(direction = all, color = color-line-1, radius = 0)
  position relative
  if direction == top
    &::after
      hairline-common(direction, color)
      top 0
      left 0
      width 100%
      height border-width-base

  else if direction == bottom
    &::before
      hairline-common(direction, color)
      bottom 0
      left 0
      width 100%
      height border-width-base
    
  else if direction == left
    &::after
      hairline-common(direction, color)
      top 0
      left 0
      width border-width-base
      height 100%

  else if direction == right
    &::before
      hairline-common(direction, color)
      top 0
      right 0
      width border-width-base
      height 100%

  else
    &::after
      content ''
      position absolute
      top 0
      left 0
      width 200%
      height 200%
      border solid border-width-base color
      box-sizing border-box
      transform-origin 0 0
      transform scale(0.5)
      z-index 2
      if radius
        border-radius radius

svg-background(svg)
  background-image url(svg)

vertical-height(height)
  height height
  line-height height